Four French judges on Sunday began questioning more than 300 Indians travelling on a plane detained near Paris over suspicions of human trafficking.
The Nicaragua-bound Airbus A340 has been held at Vatry airport, 150 kilometres (95 miles) east of Paris, since arriving from Dubai on Thursday for refuelling after an anonymous tip-off that it was carrying potential victims of human trafficking.
The judges have the authority to extend the detention order being used by border police by eight days initially and for a another eight if required.
They have two days to complete speaking to the passengers.
"The goal is to be able to see everyone," Annick Browne, the prosecutor for the Chalons-en-Champagne region, told AFP.
The judges are being helped by translators.
The 303 passengers of the flight operated by Romanian company Legend Airlines are holed up in the airport. They include 11 unaccompanied minors, according to Paris prosecutors.
Ten of the passengers have requested asylum, a source close to the case said.
Tarpaulin covered the entrance hall's glass exterior and nearby administrative buildings, while police and gendarmes prevented access.
Two passengers in custody since Friday had their detention extended Saturday evening for up to 48 hours, according to the Paris prosecutor's office.
They were being held "in order to verify" whether their role "may have been different than the others in this transport, and under what conditions and with what objectives".
Investigators have checked the identity of passengers and flight crew, and are verifying the "conditions and purposes" of their travel, the prosecutor added.
The Indian embassy in Paris said Saturday that it was working for "a rapid resolution of the situation", posting on X that "consular officials are on site".
Patrick Jaloux, the head of civil protection in the Marne region, said the passengers were understandably "frustrated" after spending three nights in the airport.
He said some of them spoke Hindi, India's national language, and the others Tamil which is spoken in southern India and in parts of Sri Lanka.
"They are in touch with their families on telephone," he said.
A source close to the inquiry told AFP that some of the Indian passengers were likely workers in the United Arab Emirates who may have sought to go to Nicaragua on their way to the United States or Canada.